This invention relates to goggles for eye protection, particularly where closely conforming resilient material contacts the area surrounding the eye for the purpose of padding and/or sealing the eyepiece against the wearer's face, for activities such as swimming.
From the early part of this century designs for goggles as eye protectors have employed resilient material between the area surrounding the eye of the user, and the peripheral edge of the goggle eye piece. Early designs employed this material as cushioning for comfort, or to protect eyes from flying objects in industrial settings, or to protect from wind (e.g., Baker, U.S. Pat. No. 1,807,681 (1931).
Swimming goggles require an additional function of sealing each eyepiece against the face in a water tight manner. This is achieved by the elastic force of the head strap pulling the eyepiece against the face, and suction forces created when some air is discharged while fitting the goggles, leaving negative pressure inside the eyepiece.
It is well known in the art that these forces create pressure points and a certain amount of discomfort in exchange for a water tight fit. Greater forces equal greater discomfort, but a more secure fit against leakage.
Traditionally, the resilient material, or pad, has been defined as a gasket attached to a peripheral flange or rear frame portion of the goggle to contact the wearer's face. Lathrop, (U.S. Pat. No. 4,286,340) teaches an extension of the sealing pad to contract frame wall portions above the eye for increased comfort, while Haslbeck, (U.S. Pat. No. 4,755,040) contains a softer pad within a seal holder to prevent deformation which causes leakage. Because of the wide range in facial structure neither advancement completely addresses issues of comfortable, water tight fit. Likewise, as early as Baker, U.S. Pat. No. 1,807,681 (1931) or as late as Hall, U.S. Pat. No. 5,046,199 (1991), the cost and importance of sealing pad alignment with the correctly corresponding frame portions has been recognized.
It is also known that an adjustable and flexible nose bridge aids not only the correct alignment of lens portions in front of the eyes, but is important to seat the rearwardly facing sealing structures in a manner that will accommodate a broad range of facial characteristics.
As early as Troppman, U.S. Pat. No. 1,261,190 (1918), and as later as Hall, U.S. Pat. No. 5,046,199 (1991) ease of nose bridge assembly is a recognized factor in commercial success. However neither example is adjustable.
Flexible nose bridge straps which have projecting stops spaced longitudinally for the purpose of engaging goggle frame lugs adjacent to the nose offer adjustability of distance between eyepieces, and has been the system most used in swimming goggles since the early 1970's. Improvements to this system include Haslbeck, U.S. Pat. No. 4,348,775 (1982), and Ohno U.S. Pat. No. 4,468,819 (1984).
Runckel, U.S. Pat. No. 4,264,987 (1981) introduces a flexible strap without stops in conjunction with a mechanical adjustment system which offers unlimited spacing within a narrow range, but at greatly increased assembly and construction expense.
The art mentioned above offers shortcomings since lug structure projecting from eyepiece frame walls can come into uncomfortable contact with the side of the wearer's nose. Additionally, prior art nose straps are adjustable at both ends, creating confusion for the user.